MISCELLANEOUS PAPERS. 20:^ 



mately connected ? They exist in the same structure. Death is the 

 result of life, and life 8[)rino-8 from the jaws of death. 



We are apt to think of existence as a straight line with the origin 

 of life at one end and death at the other. It is on the contrary a circle 

 in which life and death blend into each other so imperceptibly that one 

 is not able to distinguish where the one process begins or the other 

 leav^es off. And in the vegetable kingdom it is the matured seed with 

 the embryo that completes the cycle that began in the germination of 

 the seed that produced the parent. 



The reproduction of vegetable forms is accomplished in various 

 ways : 



In the simplest i)lant8 there are no special organs of reproduction, 

 but propagation is carried on by self-division. This is true of all uni- 

 cellular forms — the division beginning in the protoplasm. The new cell 

 buds out from the side of the parent cell, and becomes detached before 

 attaining full size. 



Among cryptograms, or tiowerless plants, such as molds, mush- 

 rooms, mosses, lichens, etc., reproduction is accomplished by spores, 

 each spore being a single cell capable of reproducing a perfect plants 

 similar to the parent; while in the case of the potato, the grape, the 

 banana and the sugar-cane, cuttings are taken from root, stem or leaf,, 

 and by these reproduction is effected. But it is the higher forms, the 

 flowering plants or phjenograms, that we are especially to deal with 

 in this discussion. Here we find the special organs of reproduction 

 embraced in the flower whose function it is to produce the seed; and 

 in the seed we find the prototype of the plant in the embryo. Before 

 taking up the discussion of the completed seed it will be necessary, or 

 at least interesting, to consider the parts of the flower directly con- 

 cerned in its production. These are the pollen gram, the pistil and the 

 ovule. 



All flowering plants are divided into two classes: the gymnosperms, 

 or naked seeded plants: that is, those with an unclosed ovary, and 

 angiosperms, or those with a closed ovary. 



Of these, the angiosperms exhibit the most characteristic seed 

 development, and it is the general method of such a seed formation 

 that we will endeavor to trace, keeping in mind all the time that the 

 process is subject to almost endless variation at the different stages. 



We usually think of the flower as composed of four parts, viz, : 

 the calyx, corolla, andrtecium and gyn?ecium, or more simply of sepals, 

 petals, stamens and pistils. Of these, only the stamens and pistils are 

 vitally concerned in the production of the seed, and these, it may be 

 remarked, exist in an almost endless variety of form. 



